1. Technical Field
The present disclosure relates to a conductive film applicable to an input display unit capable of inputting information by a touch of a finger, the stylus pen, or the like.
2. Background
In the related art, a conductive film is known in which an indium tin oxide layer and a copper layer are laminated on a polyethylene terephthalate film (Japanese Laid-Open Patent Publication No. 2011-060146). The copper layer of the aforementioned conductive film is, for example, in order to manufacture a touch sensor applicable to a narrow bezel, processed to form a wiring at an outer peripheral portion of a touch panel screen (central window portion).
The aforementioned conductive film are occasionally stored for a long time in a rolled state before processing the copper layer, and in such a case, the aforementioned copper layer is oxidized naturally under the influence of oxygen in an atmosphere and an oxidized copper layer is formed in its surface. However, in a case where a film width of the conductive film is large to some extent, film characteristics may decrease since, when an oxidized copper layer is formed by natural oxidation, a difference in a degree of oxidation may be produced partially and the surface resistance value may vary in a width direction of the film.
It is an object of the present disclosure to provide a conductive film that has a smaller variation in the surface resistance value in the width direction and improved film characteristics.